Moss, in Botany, a term for a numerous family of plants, which may be called the dwarfs of the table kingdom.

Mosses were formerly supposed to be a mere excrescence from the earth, and trees, yet they are no less perfect plants than those of greater magnitude, having roots, flowers, and seeds, though no art has hitherto been discovered, to propagate them from the seed.

They are spread over the whole globe, so that in some situations the soil is exclusively covered by mosses ; and thus frequently bare rocks "gradually become fertile.-As they grow most copiously on the north-west side of trees, it is probable that mosses serve to pro-ted them from the severity of cold ; cold; but, if these parasitical plants be suffered to increase too abundantly, they tut only tend materially to injure trees, but also to stifle the more useful vegetables of the soil.

Mosses are almost constantly green ; nave the finest verdure in autumn; and, though kept in a dry place for a whole century, they may be revived, and their colour restored, by immersing; them in water.

Dry moss is the most proper substance for mattresses, and greatly superior to straw; as it is not liable to be infested with mice, bugs, fleas, etc. When such couches become hard by compression, they may be easily raised again and rendered soft, by beating them with sticks. For this purpose, however, the longest and softest mosses ought to be collected, in September, during dry weather; then cleansed from all impurities and woody roots; dried in the shade; and again agitated with a stick, on a hurdle. Next, the mattress is to be stuffed eight inches thick, and quilted in the usual manner.- Noris this soft substance less useful for packing glass, earthen ware, and other brittle articles, in preference to straw, or wood shavings.

Among the numerous mosses which are subservient to economical purposes, we shall at present only mention a few of the most useful; because others are inserted in their alphabetical place.

1. Fontinalis antipyretica. or Greater Water-Moss, which grows upon rocks and roots of trees; in- brooks, rivulets, slow streams, and ponds : it flowers from June to September.- According to'LiNNAEus, this species resists the action of fire; and, if mixed with mortar for lining the inside of chimnies, it renders them fire-proof; as, contrary to the nature of ail other mosses, it is almost iucombustible.-Bohmer also remarks, that a thatched roof, if cohered an inch thick with the. greater water-moss, will be completely secured against fire.

2. Bryum rurale, which grows on roofs, both thatched and tiled ;j walls; and trunks of trees : it is perennial, and flowers from December to April.—Thatched buildings overgrown with this moss, instead of lasting about ten years, will remain sound for a century.

3. Sphagnum palustre, or Grey Bog-moss, which is also perennial, and flowers in July and August.— This species materially contributes to the production of peat or turf; so that in process of time, bogs and morasses are converted into beautiful meadows .—in Norway, it is employed for filling up the crevices of planks in wooden walls ; and, .though it be sometimes used for a similar purpose in tiled roofs, yet as it affords shelter to vermin, we conceive, it might more safely and advantageously be applied behind the stones or brick-work of wells, to prevent the clay or loam from being wasted by the action of the water.

4. Byssus candelaris, L. (Lichen flavus of WitheRing), or Yellow Powder-wort ; an annual vegetable dust generated on old pules, the cracked bark of trees, and antique walls, in all parts of the world : it appears from September to June.—This powdery substance may, according to Bohmer, be employed for dyeing a very brighti-yellow colour.

5. Lycopodium cluvatum. See Clue-moss, the Common.